shoes for many
generations. Photograph from Dr. Gorgy Sobhy, School of Medicine,
Cairo.]

The question of inherited immunity to diseases, as the result of
vaccination or actual illness from them, has appeared in the controversy
in a number of forms, and is a point of much importance. It is not yet
clear, partly because the doctors disagree as to what immunity is. But
there is no adequate evidence that an immunity to anything can be
created and transmitted through the germ-plasm to succeeding
generations.

In short, no matter what evidence we examine, we must conclude that
inheritance of acquired bodily characters is not a subject that need be
reckoned with, in applied eugenics.

On the other hand, there is a possible indirect influence of
modifications, which may have real importance in man. If the individual
is modified in a certain way, in a number of generations, even though
such a modification is not transmitted to his descendants, yet its
continued existence may make possible, the survival of some germinal
variation bearing in the same direction, which without the protecting
influence of the pre-existing modification, would have been swamped or
destroyed.

Finally, it should be borne in mind that even if physical and mental
characters acquired during a man's lifetime are not transmitted, yet
there is a sort of transmission of acquired characters which has been of
immense importance to the evolution of the race. This is the so-called
"inheritance" of the environment; the passing on from one generation to
the next of the achievements of the race, its accumulated social
experience; its civilization, in short. It is doubtful whether any
useful end is gained by speaking of this continuance of the environment
as "heredity;" it certainly tends to confuse many people who are not
used to thinking in biological terms. Tradition is the preferable term.

There is much to be said in favor of E. B. Poulton's
definition,--"Civilization in general is the sum of those contrivances
which enable human beings to advance independently of heredity."
Whatever wisdom, material gain, or language is acquired by one
generation may be passed on to the next. As far as the environment is
concerned, one generation stands on the shoulders of its predecessor.
It might simplify the task of eugenics if the same could be said of
biological heredity. But it can not. Each generation must "start from
scratch."

In August Weismann's words, the